Floating dry-dock



WM. THOMAS, OF ST. LOUIS, MISSOURI.l

FLOATIN'G- DRY-DOCK.

Specification of Letters Patent No. 1,609, dated Mayv 19, 1840..

To all whom t may concern:

Be it known that I, WILLIAM THOMAS, of the city of St. Louis and State of Missouri, have invented a new and Improved Mode of Constructing and Using the Improved Floating Dry-Dock as patented to J ames I'I. Peck, Robert IVash, William Thomas, and John D. Coalter by Letters Patent dated March 26, 1834; and I do hereby declare that the following is a full and exact description.

My dock consists of seven distinct floats of equal dimensions and all constructed in the same manner and are represented by lplates I, II, III, with references accompanying this description and making a part of it, viz:

Plate I, Figure l, is an interior side View of a single ioat with upright trunks, cradle timbers R, and blocks upon which the boat or vessel rests when raised, diagonal braces T, and king-posts, attached to the sides of the floats byl dowels and firmly bolted, these braces are intended to give additional strength to the sides of the floats and to throw a portion of the weight of the boat or vessel from the center to the ends of the float; Fig. 2, a side view of the dock formed by the connection of seven floats by means of string timbers placed lengthwise with the dock; Fig. 3, a view of the top and deck of the dock, with the connecting timbers P, position of the cradle timbers R top of the upright trunk and stage on the outside of them for men to stand upon to work the pumps. Plate II, Fig. l, is an interior side view of ay single float with references; Fig. 2, the deck frame of a single float with references; Plate III, Fig. l, is an interior side view' of an upright trunk and end of the' float with references; Fig. 2, exterior view of that portion of the trunk above the deck of the dock and facing toward it, as also'the frame work and plank of that part extend- "ing from the deck to the bottom of the float forming one of the bulkheads, which divide the iioat into several chambers; Fig. 3, a view of the bottom frame positions of the water pipes, bulk-heads and stanchions between them. i

Mcm/rter of construction-The sides of the iioatsare formed of three or more pieces of solid oak timber ten inches thick, tongued, grooved and doweled and firmly bolted upon each other; with heavy diagonal braces on the outside as represented and described Plate I, Fig. yl. Theends of the floats are from 6 to 8 inches thick put together in the same manner as the sides; the Vbottom-fand The bottom plank 'are .Offs Y plank are of yellow pine, all

the iioats .into several chambers, 'are formed by stanchions and planked with =two--inch oak, and made tight by calking. The ends of the upright trunks corresponding with the side of the float are of oak 6 to 8 inches thick, the side being planked with inches thick,

The ballast cisterns 0, are represented in Plate III, Fig. 1, andfoccupies that space pine/2' within the shaded lines n n, and are-formed-j within the trunks by means of a frame work across the narrowest `way of the trunk, planked with pine and made watertight byl calking. The capacity of them may be made more or less as deemed most proper or necessary and-they maybe made and attached `to the outside of the trunks.

Cleats are nailed to the frame work with- 'I in the pump-well and cistern as represented in Plate 3, Fig. 1, and VPlate 2, Fig.' l, -forl the `purpose of ascendingand descending, v openings or shutters V, Plate III, Fig. 2 are v left in the 2d and VSd'bulkheads from Yeach end near the top suiiiciently large for-'a man;

to pass through and are closed and 'madelv tight when the dock is in use. 'A small har-,hwy w Piate .1, Fig. s, 1S left inthe deck of each oat at each end between the 1st and 2d bulkheads, of sufficientsize forV a man to pass, which hatchways vare secured and calked when the dock is in use. Y

The floats thus constructed are arranged side by side as represented, Plate I, Figs.

2 and 3, and placed at such distance from of the boat or vessel to be raised, using no n more of them than may be necessary, and A are firmly connected by the string timbers P, passing through the bits or timber rheads S', Plate II, Fig. l.

Mode of operaitz'oaK-The opera-tion of this dock is by letting water into the pumpwells D, at each end of each float by means 'l of a cock F, turned by an iron rod G,wl1ich 100 f5 each other as to suit the weight and length v extends to the `top of the trunk, and from the wells into the several chambers through the several pipes H H H, Plate 3, Fig. V3, which pipes are opened and shut by rods I, Plate 2, Fig. 1, extending to the top ofthe trunk, and blocks or wooden cocks K Plate 2, Fig. l, Yand by' pumping fromv the wells to the ballast cisterns, the dock gradually sinks to the required depth to admit the boat or vessel to pass free over the blocking previously arranged to suit her bottom', the water is then shut off, the boator vessel being. placedvand secured in her proper position,: the pump-ing is commenced. and continued until the deck of the dock is raised 2 or 3 inches above theV water. During the process lofsinking or raising the dock, `the water is so regulated' by letting it into the Vwells andfrom them to the chamber,- and by pumping into or discharging ffrom'the ballast cisterns as to lpreserveV at all times an equilibrium.V It V ,will be readily seen additional means` of keeping up an equilibrium, an operation however, that hasnever yet been found necessary inthe rais-` ing of steam boats, and 'by av discharge of water from them on deck near the bottom by simply drawing a plug the dock is as sisted in raising. Y

Thei peculiar advantages ofthis kind of dockarezlst. Thesuperior strength, sim-` plicity and cheapness of construction.` 2d.

Theease andsafety with which it is man-1. aged. 3d. The ready means within itself of rep-airing,V by detaching Y the floatV requiring repair and raising: it Vupon the others. 4th. The convenience of attaching and detaching thefloats using as many only as may be` necessary for the boat or vessel to be raised.`

5th. The raising of theboat or vessel Ywith perfect safety and fwithout straining any part.` 6th. The means of straightening v a 4boat or vessel that has become fhog'ged or twisted, which may be easily done by raising or sinking one or more iioats or either end of them. 7th. The Ygreat comfort and convenience to the workmen, having a clean and dry deck to work upon, a free circulation of air, by which a vessel-is sooner madej sufficiently dry to work upon, and alwaysrlight sufficiently ample for work on all the outer side of the vessels bottom. 8th. There being no necessity, of discharging a greater quantity of water than is equal to the weight of the boat or vessel to be raised, added to v that admitted for the purpose of sinking the dock to the required depth.` QthfThe convenience and safety ofv detaching the oats and `placing them` sidewise along'shore as a security against ice in exposed situations in winter. Y l

The nature of my invention and improvevments I will now proceed todescribe with reference to the improvedyfloating dry clock,

invented by Capt. `John `Thomas and patented to James H. Peck, Robert Wash, William Thomas and John D. Coalter and as describedV in the specification attached to said patent, showing in what my inventions, improvements and differences of construction consists and in what vmanner they diHer from said specificationsy y Y y 1st. In the construction and use of a ballast cistern, formed in each of the upright trunks, the uses ofwhich are `fully explained in the mode of operation of the dock, and are substituted in lieu of the float wellsand wellv` floats, with their appendages described in said specifications here referred toas being placed in each endof each trunk, which float wells, communicated with the pump wells and chamber.

p 2d. In dividing that .part ofthe floats bei tween the wells at each end, into sixcham- -bers of different dimensions :decreasing the capacity of them, toward each end ofthe float and by making Veach chamber water tight, inthe specifications here referred to there arebut four .chambers` mentioned.. the middle bulkhead ofthe float only, being considered as absolutely necessary, and none of them were made tight, it being ,declared as unnecessary that they should be so, souttles were left-open through them sufficient .for a manto Vpass through; .experience has proved theV actual necessity of having all the bulkheads `tigglinf-that unless they are Vso the dock cannot'be controlled and is `entirely i unmanageable. The dock is easily managed and without any diflicultybythe increased iio i numberof chambers, by making them tight l v and by decreasing their "dimensions toward the` ends of the floats; thenumber however may be `moreor less thansix. p

3d. In `the use of pipes to convey the water `from the well tothe several chambers, which pipesareplaced on the topof the floor or bottom timbers and are more fully de- 'scribed` in the mode of operation of the dock.

And inthe use of airpipes LLL, Plate 2, Fig. 2, forming a communication between :the several chambers and the upper part of the well, by which the air escapes from the chambers while they are filling `with water, which air pipes are let into the top ofthe deck timbers so as Vto be secured by the vdeck plank and are bent at ,the point where they izo@ enter the well and raised perpendicularly a short distance above the level of the deck.

4th, .In having substituted one common copper pump Worked With a brake in place of the tWo Wooden pumps Worked With a pendulum as described in said specifications.

5th. In discharging the Water from the pump near the deck of the dock under Water by the spout M, eXcept When lling the ballast cistern, instead of raising it to the top of the pump by Which means more than one half the labor of pumping is saved having a much less Weight of Water to raise.

6th. In dispensing with the use of all other ballast than that of Water thrown into the ballast cistern, which may be increased or diminished as circumstances may require in the manner described in the mode of op erating the dock.

7th. By the admission of Water into the floats at the ends by means of a cock, in lieu ofy its being let in through a hole in the bot tom and stopped or regulated by a plug as described in said specifications.

8th. In the connecting of the floats by string timbers passing thro-ugh bits or timber heads in lieu of the iron links and eyes described in said specifications.

What I claim as my invention and desire to secure by Letters Patent is- 1. The employment of the ballast cistern in combination With the floats in the manner herein described.

2. I also claim the making vof the bulk* heads, Which separate the chambers, Water tight so as to prevent the Water from passing from one chamber to another except through Y the dock together with my improvements,V 'Y

such as will enable any competent'workman to construct the same, I would haveit understood that I do not mean to confine myself to the precise form, dimensions, or number of flo-ats and their appendages but to vary the same While I attain the same ends by means substantially the same.

` INM. THOMAS.

Witnesses D. D. DAVIS, THos. B. HUDsoN. 

